Chemistry Reference
In-Depth Information
Figure 27.1
(a) Interaction partners of selectin -
mediated cell -cell contacts between leukocytes/
lymphocytes and vascular endothelial cells. (b)
Mechanism of selectin interactions during vas-
cular adhesion and extravasation of leukocytes
to infl ammatory tissue.
receptors (Figure 27.1b). During the next step leukocytes/lymphocytes have to
extravasate by transmigration induced by chemokine gradients (diapedesis), and
then move along a gradient of chemoattractants to the source of infl ammation
where they fi nally fulfi ll their task of anti-pathogen immune attack (please see also
Figure 29.5 ).
27.2
Where Do Carbohydrate-Lectin Interactions Play a Role
During Acute Infl ammation?
We focus here on the most pertinent effectors involved in mechanisms of infl am-
mation and lymphocyte activation. Components of the innate immune system like
the complement system, in which carbohydrate interactions play a role both for
initiating the complement cascade (lectin pathway) and for controlling the effects
of complement-mediated cell destruction (like inhibition of C1q, the fi rst element
of the classical complement pathway, by chondroitin sulfates) are not dealt with
here (please see Chapter 19 for lectin in innate immunity). There are three major
families of lectins that play an important role in immune reactions: the selectins,
the galectins and the siglecs.
